Apple 1705 Display Computer Monitor User Manual

Resetting controls to the factory settings
The picture controls for your display are set at the factory. You can fine-tune
the picture and make adjustments if necessary. The display will use your
adjusted settings each time you turn on the computer. If you later decide you
want to revert to the Macintosh factory settings, press the Down and Up
buttons at the same time.
Adjusting the Picture